Invalid code generated for classes in the empty package #182

/**
  * test model
  * @param field some field des
  */
case class ScalaModel(field: String)

public  class ScalaModel$ extends scala.runtime.AbstractFunction1<java.lang.String, <empty>.ScalaModel> implements scala.Serializable {
  /**
   * Static reference to the singleton instance of this Scala object.
   */
  public static final ScalaModel$ MODULE$ = null;
  public   ScalaModel$ ()  { throw new RuntimeException(); }
}